package top100;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;

/**
 * @author Godc
 * @description
 */
public class ThreeNumSum {
    public static void main(String[] args) {
        ThreeNumSumSolution s = new ThreeNumSumSolution();
        List<List<Integer>> lists = s.threeSum(new int[]{-1, 0, 1, 2, -1, -4});

    }
}
class ThreeNumSumSolution {
    public List<List<Integer>> threeSum(int[] nums) {
        List<List<Integer>> res = new ArrayList<>();
        // 排序
        Arrays.sort(nums);
        for(int i = 0;i<nums.length;i++){
            if(nums[i]>0) return res;
            if(i>0&&nums[i]==nums[i-1]) continue;
            int cur = nums[i];
            int left = i+1,right = nums.length-1;
            while(left<right){
                int sum = cur+nums[left]+nums[right];
                if(sum==0){
                    List<Integer> list = new ArrayList<>();
                    list.add(cur);
                    list.add(nums[left]);
                    list.add(nums[right]);
                    res.add(list);
                    while(left<right&&nums[left]==nums[left+1]) left++;
                    while(left<right&&nums[right]==nums[right-1]) right--;
                    left++;
                    right--;
                }else if(sum<0){
                    left++;
                }else{
                    right--;
                }
            }
        }
        return res;
    }
}